1. Field of the Invention
The present invention relates to a releasing composition suitable for electrophotographic toners (hereinafter referred to as toner). More particularly, it relates to a releasing composition for toners, particularly suitable for those used in copy machines or printers of the heat fixation type.
2. Description of the Background
Toners, in heat fixation methods, are fixed on a substrate with a heated roller. In these methods, it is desired that the minimum temperature for fixing (hereinafter referred to as MF) is low and the hot offset temperature (the temperature causing offset to the heated roller) (hereinafter referred to as HO) is high. In order to meet these two requirements, it has been proposed in the past to add a releasing agent such as low molecular weight polypropylene to the toners during the preparation to attain an elevated HO. In these techniques, there are drawbacks, one of which is that a releasing agent such as a low molecular weight polypropylene results in poor toner flowability (hereinafter referred to as TF), and that sufficiently high HO is not always obtained. In order to remedy these drawbacks, research has been conducted which has resulted in the proposal to modify the toner with a carboxylic acid or anhydride thereof. Such modified low molecular weight polypropylenes, however, are not put to practical use because the HO may be reduced, though reduction of TF can be suppressed.